IN RECENT YEARS, I'VE TESTED QUITE A FEW systems that let drivers chat away legally on their cellphones hands-free. While ear-plug versions have reached near-perfection ( I am thinking particularly of the Aliph Jawbone), systems that work through the car's speakers have never quite come up to scratch, always lacking clarity or volume. The Jabra SP700 is not perfect, but it's better than anything else out there.

The palm-sized unit looks good and attaches firmly to the sun visor above the driver. Linking the unit to a Bluetooth cellphone couldn't be easier. When you get a call, all you have to do is press on the front of the Jabra to speak. You can listen to your callers either through the Jabra or your car's speakers -- since the Jabra can transmit FM signals to your radio.

Thanks to its noise-reduction technology, voice clarity is, well, good -- perhaps even better than good. In the course of about 15 calls, only two people said they couldn't hear me well. While I would have liked to have been able to boost the maximum volume, I could hear everyone well.

Thanks to the device's prowess as a radio transmitter, you can also stream music stored on your phone to the Jabra and on through to your car speakers. In this mode, happily, I could turn up the volume as loud as I wanted.